Erratic Idle, Fluctuating when using Electronics

[CharvelM2]

Hello, I am new on this forum and have bore this problem for about a month now. My 1988 Honda Accord DX idles fine during the day with little to no fluctuation (without any electronics on). However, when I try to drive during the night time and I turn on my lights, heat, and even when I try to make turns my idle will plummet into the low 200-400 range and then fight its way back up or even just stall. This idle fluctuation is only present either when 1) my car hasn't properly warmed up and I try to drive it or 2) when I have the electronics on. Could anybody help a lost soul here?

[Dr_Snooz]

Start with a bottle of injector cleaner. See how that does. Failing that, you probably have some carb issues you'll have to sort out sooner or later. When was your last tune up?

[CharvelM2]

I ran a bottle of carburater cleaner about two months ago, replaced the plugs, air filter, and wires around the same time as well. I just find it wierd that this problem is as a result of the electronic usage of the car. If I turn the wheel two turns, the idle plummets to 200 but if I straighten it its golden. If I turn the lights on, it goes down to 200-300 as well.

[Dr_Snooz]

Probably need a carb rebuild. We're getting a lot of dying carb questions right now. I guess they're all wearing out. You can sit down with the manual (http://honda.roadpwnage.com/manuals/pages/usdm-accord-1989-full.php) and try to find the specific bad parts (but you probably won't). You can buy a rebuilt carb (lots of $$$$). You can try to rebuild it yourself (they are notoriously difficult to get right). Or you can swap in a Weber (and not pass any more smog tests). There aren't any really good options as you can see.

I don't think the electronics have anything to do with it. It's putting load on the engine at idle. You shouldn't just take my word on the carb, of course. Use the diagnostics in the manual to rule out a possible bad coil or plug wire, etc. If everything checks out, then you'll be looking at the carb again. I'm not sure if there is a module that is supposed to correct for additional load at idle, but if there is, that would be the place to start looking. My personal opinion is that a carb needs to be completely overhauled when it starts messing up. Some guys on here have had good luck fixing individual parts on their carbs though.

Hopefully someone better with carbs will weigh in with a second opinion here.

[g.frost]

There's nothing in the service manual about adjustment for alternator draw when electrical accessories are on. (like there is for A/C and Automatic transmission) In fact, the procedure to set idle speed and mixture specifies to have the electrical stuff off. It sounds like you may need to adjust the idle mixture and speed. The book describes the procedure using propane enrichment. It sounds like it may be running too lean. But this could also be caused by any number of vacuum leaks.

I checked on my car; idle speed dropped about 50-60 rpm when turning on headlights, blower, and rear defroster, 750 to 700 rpm or so.

If it is a momentary dip when first coming down to idle, it could be the dash pot.

If you try a fuel system cleaner, don't bother with a solvent type, mostly useless. Use something with a good dose of PEA like Redline or Techron.

[g.frost]

Something you could try with spray carb cleaner like B-12 Chemtool:

Remove air cleaner cover and screen over carb. With warmed up engine, spray a good dose of carb cleaner directly into float tank. (via vent tube, sticks up at an angle )
Let the engine idle for a good bit to force this concentrate through the idle control mix valve(s). Might want to rev it a bit to clean out the rest of the jets too while your are in there. If it is gum or deposits in idle control, that may just do the trick.

[Demon1024]

Upgrade / beef up your ground cables and get back to me.....
common problem

[CharvelM2]

So I did change the ground line, and that did not solve the problem. I am going to get another can of carb cleaner to see if that will solve the problem, but probably not.